It could have easily been overlooked. It was not the first time a young, frustrated Arab had taken desperate action to draw attention to the plight of the marginalised millions. But on this occasion the news of a suicide went viral.

A year to the day since Mohamed Bouazizi's self-immolation in a sleepy Tunisian town kicked off a year of revolt, the convulsions have spread further than could ever have been imagined: in the depths of a Russian winter activists are planning their next howl of protest at the Kremlin; in a north American city a nylon tent stands against a bitter wind; in a Syrian nightmare a soldier contemplates defection.

Quietly, a lifetime of old power structures – political, social, ideological – have been dissolved and the certainties of one generation have been replaced by the messy unpredictability of another. Today the furniture of the new sits deliberately beside the supposed certainties of the old. Handmade barricades are bolted to public squares, plastic tents pitched beside stone cathedrals, and the solid steel of a New York bank is harassed by pop-up armies of retweeters.

It began as a Mediterranean revolt spreading on both sides of the sea – from Tunisia through Egypt and Libya and beyond, and from Greece and Spain upwards into Europe. In a million different and fragmented ways, scenes of protest were the narrative backbone to 2011 played out again and again in cities as far afield as Santiago, Stockholm and Seoul.

But to view the activism of 2011 through a nationalist, ethnic or even class lens is to miss its unifying trait – 2011 was the year of a global youth revolt.

The struggles that gave birth to each demonstration, occupation or revolution were separate and yet connected; part of a collective roar from young people who, for the first time in modern history, faced a future in which they would be worse off than their parents.

Kyriakos Chatzistefanou, Greek journalist and director of documentary Debtocracy, says it was exactly this awareness that got people into the streets of Athens. "It was mainly middle-class, well-educated people that felt for the first time that they will be what economists now call the lost generation.

"That was a paradigm shift. With small intervals in the second world war and the dictatorship, in general all the generations in Greece had growth and a better future. For the first time after 2008 there is a generation that realises that there is an end to that … [and] they reacted angrily, violently."

The same prognosis is to be found on the other side of the Atlantic. The lack of opportunities for young Americans has been "a huge part of what's happening", says Laura Long, who has been involved in Occupy Oakland since September.

"We were promised a series of steps on a ladder to climb to get to a point to be successful, and in the last decade especially that ladder has just been pulled up so that we can't even reach the lowest rung basically."

But it is far more than material privation that underlies this year's youth revolt, more than just a question of how to integrate into the globalised economy the talents and expectations of 80 million unemployed young people from the most well-educated generation in human history.

At the heart of this most potent insurrection since 1968 is an expression of the deep uncertainty about how the future will pan out.

"It's the first time in American history that a generation came along and was told: 'No, things are gonna be worse for you than they were for your parents'," says Jesse LaGreca, a prominent Occupy Wall Street figure who has travelled to occupations across the US.

"I think that has created the necessity for change, and we can no longer wait for political promises – we have to make that change ourselves." And the social problems run deep.

In the US the current crop have been called the boomerang generation due to young people's inability to flee their parents' nest.

The data underscores the problem: more and more young people out of work, more and more of them stuck living with their parents well into their 30s. One in five American men between the age of 25-34 have not yet left home. In Europe the figure is even higher. For Vesna Milosevic, a Slovenian expert on youth employment, statistics like these demonstrate the frustration that young people have with becoming independent adults.

"Young people are postponing the important events or phases in their growing up process. For example, they get a job very much later … but at first they are stuck in some precarious work or a temporary job.

"The period of 'youth' is extending to the 30s or even towards 35. They have children later … and [are] moving away from their family and becoming independent later, which is the most important thing.

But, she says, "they don't want to be in this 'mama hotel' … they have no other choice. This postponement is not voluntary. It's the [economic] situation which forces people to postpone events in their life. It's too expensive to rent an apartment if you don't have a regular job, if you don't know what's going to happen next month," she says.

With the ability to build horizontal links using new technologies, a generation decided this year not to passively embark on a pre-programmed conveyor belt of life under austerity, oppression – or both – but instead opted to come together and attempt an audacious reclamation of autonomy.

Nowhere was this more true than in the Middle East, where Bouazizi's immolation set off an inferno that is still smouldering. On Friday in Cairo, as demonstrators and police again clashed violently, it was as clear as ever that there is plenty of unfinished business in this youth uprising.

"The Arab world was considered a stagnant pond of retardation and tyranny, inhabited by what appeared to be a complacent populace toiling fatalistically under the yoke of their dictators," says Iyad el-Baghdadi, compiler of the canonical Arab Tyrant's Manual.

"Most observers thought this status quo to be stable, if not permanent," adds el-Baghdadi. "What's worst, many Arabs thought so too. Boy, look at us now."

When you speak to those organising the Occupy movement, it is remarkable how important Tunisia and Tahrir were to their own action. No longer was the west to be a democratic beacon to the Middle East. It was very much the other way around.

"Who would have thought that Mohamed Bouazizi would set in motion such a series of events?" says David Osborn from the Occupy Portland movement. He says that many in the west were "deeply moved and inspired" by seeing protests across the Middle East, but that Egypt in particular had captured Americans' imagination.

"To see the movement generally, but in particular the youths, mobilise and really demand the impossible … to think Mubarak would not have been president more than a few weeks or even a month or two before he actually fell was almost impossible. And yet they asserted that another world without Mubarak was possible, and I think that kind of re-inspired the radical imagination in many of us."

"The lesson of Tahrir Square was that once again, democracy has become a revolutionary force," says Shimri Zameret, who spent four months organising the global day of occupation on 15 October that saw people in more than 900 cities turn the square's tent city into a worldwide phenomenon.

Zameret, who also spent two years in an Israeli jail for refusing to serve in the army, says young people have suddenly reached a tipping point in their acceptance of the status quo.

Suddenly "the natural, everyday has become the historical", he says, adding that there is an awareness that "things can change and change suddenly" when people take to the streets. Civic action, he says, brings a sense of control back into people's uncertain lives.

Zameret also talks of an infuriation at the way the global leadership has failed to tackle the pressing issues of the day, from corporate greed and banking failure to problems like the environment.

"The demand [by activists] is no longer to go to the IMF or the G8/G20 summit and beg to have this or that issue implemented, it is also not about 'anti-globalisation'. This time it's about 'real global democracy now': we demand the power to fully control the decisions that shape our lives – local, national, European and global."

It is easy to dismiss the interconnectedness of 2011's youth-driven resistance movements; and it is possible even to deny they amount to any kind of identifiable social phenomenon at all.

Certainly, comparisons between the pepper spray of Oakland and the tank shells of Homs can be facetious, and the triumphs of the protester – named this week as Time's "person of the year" – appear scant if limited purely to the arena of formal political change.

But connections there are, not just in mutual recognition and frustration, but in method. The movements that made the headlines in 2011 were largely non-hierarchical, creative and locally autonomous. And consciously so.

Occasionally, a leadership figure peeks through – like Tawakkul Karman in Yemen, Camila Vallejo in Chile or Alexei Navalny in Russia. But on the ground appointed leadership has, it seems, become a shunned concept for fear those at the top of a social movement would soon bow to and barter with an old guard.

As Ganzeer, one of Egypt's most popular street artists, argues, Tahrir has been swamped by all manner of those who speak the language of change but seek ultimately to suppress it by cutting deals with those on the other side of the gate.

"Demonstrations, strikes, and other forms of protest carry on regardless, because today's revolution, unlike revolutions of the past, is leaderless," he claims.

Andres Villena Oliver from the Indignados movement in Spain admits that it is not easy. "It's a very emotional process," he says. "They don't just feel very angry with the economic failures but they want to change the world, in some weeks. It makes it very difficult.

"The more democratic a movement is, the less efficient it is."

But people will be heard, he says, and on an equal footing as everyone else.

A new political form is being cobbled together by those on the street, and it has come to reflect the horizontal lines of the social media which helps drives so many of today's demonstrations.

But the great revenge is this: the generation that grew up being told they were the heirs to Francis Fukuyama's end of history and victory of a liberal capitalist society, is now working its damnedest to prove how untrue this is, not for the sake of utopian reimagination but to resolve the very serious problems that very system has created.

Where the movement goes next remains to be seen. But as the Jordanian human rights activist Laila Sharaf recently told a group of young people in Beirut, in a statement that could apply universally: "Today the rules of the game have changed, and the ball is in your court."

Or, to put it in the words that are so often held aloft at any street protest today, part in hope, part as threat: "This is just the beginning."